[according to Brewer from the name of a tailor.] An overcoat of a particular shape formerly worn by men. (Still in slang or humorous use.)

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1817.  T. L. Peacock, Nightmare Abbey, 159. His heart is seen to beat through his upper benjamin.

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1837.  Lockhart, Scott (1839), V. 59. A vastly scientific and rather grave professor in a smooth drab benjamin.

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1841.  Punch, I. 98. This coat is, in fact, a cross between the dress and the driving, and may, perhaps, be described as a Benjamin, junior.
  Of the Benjamin, senior, there are several kinds—the Taglioni the Pea, the Monkey, the Box, et sui generis.

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1865.  Pall Mall Gaz., 7 March, 3/2. [quoting East-end slang].

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